Out of curiosity, what does minimal desktop give you as a desktop? Matchbox? That's the one I remember.

CentOS has usually offered a relatively small choice of desktops though I suspect that once 7 has been around for awhile, various 3rd party repos will offer several of them. So far, in 7.x, I've just compiled dwm on it. (A very small tiling window manager desktop that requires very few dependencies.)

after installing "Minimal Desktop" under CentOS-6, you have GNOME2 with a set of minimal packages and programs. This is useful, if you need a server and a graphical set of programs,like for example virt-manager.